planar mates

I want to put a mate connector in between these entities in order to make a revolute mate with the center of the cylindrical axle. I was previously using a slider mate in conjunction with a planar mate (mate connector between the angled bar), but the rack and pinion relation doesn't allow me to select slider mates (despite…

So, I had an assembly built out and working fine. I made a few changes that blew up the assembly and now, nothing seems to be working. Trying to do a simple planar mate results in nonsensical mates to items not even clicked. In the image below, the bottom surface of the fitting is affixed to the square insert in the ring…